How Do You Remove Flux After Brazing? “A Time Saver’’ Will be discussed in this article.
How do you remove flux after brazing?
There are different ways to remove flux after brazing.
One way is soaking the joint in water, you can also use a wet towel or a wire brush to clean excess flux of a brazed joint.
Brazing flux is an essential part of brazing and welding, as we have seen in another article called ‘What Is brazing flux and how to use it?’
This article is about removing excess flux after the brazing process and why it is necessary to do. So, without further ado, let’s get started.
What Is Flux For Soldering?
Before we can dive into the intricate details of flux removal, we need to take a step back, because what is flux for soldering, brazing, and welding in the first place? Let’s find out.
Flux is a chemical that should be added during the brazing process.
This chemical affects the joint to prevent corrosion and form a stronger bond between the metal pieces. Flux isn’t necessary but highly recommended.
How Do You Clean Excess Flux?
As we have seen in the previous paragraph, flux is an essential part of the brazing process. However, too much flux can have negative consequences. This leads to the question, how do you clean excess flux?
There are many different ways to clean excess flux.
The most common way is to use a cloth with a cleaning solvent such as alcohol to rub away the excess flux. You can also bathe the joint in a cleaning solution to get rid of excess flux in no time.
What do I use to remove the leftover flux?
I use Sparex pickling compound it removes most of the surface oxidation and scales on everything silver and copper.
What Happens If You Don’t Clean Flux?
We have now seen different ways to remove excess flux from your brazing joints, but why should this be done in the first place? Let’s take a look at what happens if you don’t clean flux.
If the flux is unnecessarily left on a brazed joint it can cause corrosion and weaken the joint, therefore eliminating its positive effects.
This is because the flux is a reactive chemical and it shouldn’t be left on metal for too long.
What Is No Clean Flux?
You might have heard of the term no-clean flux, as it is often used in the world of brazing. But what is no clean flux, and do you need to remove no-clean flux? Let’s find out.
No clean flux is a type of flux where the amount of flux left on the joint is negligible to the point where it does not need any cleaning or removing at all.
This is useful for obvious reasons, and no-clean flux is therefore commonly used.
Which Material Is Used For Removing Residual Flux?
As we have briefly mentioned before, the excess flux will need to be removed to avoid any negative consequences on the brazing joint.
But what material should we use for this flux removal process and how does it work? Let’s find out.
There are many chemicals that can be used to remove residual flux. Usually, acids (Sparex pickling compound) are used for the cleaning process.
Isopropyl alcohol will also do a great job at cleaning residual flux. Any cleaning agent will do the job.
How Do You Remove Flux After Welding?
Flux is not only used when brazing or soldering, but flux also plays a large role in the welding process.
The same rules surrounding flux cleaning and removal apply for welding, but how do you remove flux from a large welding joint? Let’s take a look.
Removing flux after welding works pretty much the same as brazing.
Simply use a cleaning agent such as acid or alcohol and a wire brush to clean off and remove the remaining flux.
Welding joints are usually bigger than brazing joints, so use the appropriate amount of cleaning.
How Do You Clean A Brazed Joint?
As we have previously mentioned in this article, flux plays a huge role in brazing joints. Of course, brazed joints also need cleaning, but this raises the question, how do you clean a brazed joint? Let’s take a look.
Cleaning a brazed joint is similar to the other cleaning methods mentioned in today’s article.
Use a wire brush, Sparex pickling compound, or a cloth drenched in a cleaning agent to wipe of the excess flux from the brazed joint. Further cleaning can be done using water as a final rinse.
Can You Use Mechanical Cleaning Methods To Remove Flux?
So far, we have been talking about so-called chemical cleaning methods. This involves the use of chemicals to clean a surface, in this case, flux.
But this raises the question, can we use mechanical cleaning methods instead of chemical methods to remove flux? Let’s take a closer look.
In theory, it is possible to use mechanical cleaning methods like a wire brush to remove flux. However, chemical methods are recommended as they are guaranteed to remove all of the flux.
Mechanical methods should work, depending on the method you use of course. Sometimes I use both methods.
Final Thoughts On… How Do You Remove Flux After Brazing? “A Time Saver’’
All in all, flux is an essential part of brazing and welding, but if you don’t take proper care of flux removal it can have counterproductive effects.
In this article, we have discussed several ways of cleaning and removing excess flux. Thank you for reading and good luck with your flux.
If you enjoyed How Do You Remove Flux After Brazing? “A Time Saver’’ You will Love What Is Brazing Flux And How To Use It?
Frequently Asked Questions
Let’s finish off by looking at some frequently asked questions on the topic.
Can I use Ultrasonic cleaning to remove flux?
Yes, you can, it is however often used as a final step in the cleaning process.
Should you clean off Flux?
Yes, you should clean off excess flux to prevent oxidation and form a stronger bond.
Can you solder without Flux?
Yes, you can solder without flux, it is not recommended however as oxidation may occur and the bound will be less strong.
What is flux remover?
Flux remover is a chemical specialized in removing flux, it is very useful to remove flux quickly and effectively.
Does Isopropyl Alcohol clean flux?
Yes, isopropyl alcohol is a great cleaning agent for light amounts of flux
Sources In MLA Format
Experts, Lucas-Milhaupt Brazing. “Flux Removal: Post-Braze Cleaning.” Flux Removal: Post-Braze Cleaning, https://blog.lucasmilhaupt.com/en-us/about/blog/flux-removal-post-braze#:~:text=The%20most%20common%20methods%20for,spray%20bottle%20or%20wet%20towel.
“How Do You Clean Excess Flux?” Chemtronics, https://www.chemtronics.com/how-do-you-clean-excess-flux#:~:text=The%20most%20common%20way%20to,it%20around%20the%20repair%20area.
user49674user49674 16322 gold badges22 silver badges66 bronze badges, et al. “Why Do We Need to Remove Flux from Circuit Boards?” Electrical Engineering Stack Exchange, 1 Sept. 1963, https://electronics.stackexchange.com/questions/170941/why-do-we-need-to-remove-flux-from-circuit-boards#:~:text=Fluxes%20are%20reactive%20chemicals%2C%20and,circuits%20with%20high%20reliability%20requirements.